KR101735857B1 - high voltage lithium rechargeable battery - Google Patents

Abstract

The present invention relates to a positive electrode for a lithium secondary battery and a lithium secondary battery comprising the same, and more particularly, to a positive electrode for a lithium secondary battery which can improve a high temperature storage characteristic of a lithium secondary battery by containing a novel positive electrode additive, To a lithium secondary battery.

Description

[0001] The present invention relates to a high voltage lithium rechargeable battery,

The present invention relates to a high-voltage lithium secondary battery, and more particularly, to a high-voltage lithium secondary battery including an aromatic amine derivative as an additive and used in a lithium secondary battery having a working voltage of 4.3 V or higher.

New energy sources have been intensively researched due to changes in the industrial environment seeking environmentally friendly energy. Particularly, researches on a lithium secondary battery which can provide a stable power supply while exhibiting high energy density and high performance as a main power source or an auxiliary power source of an electric vehicle or a hybrid vehicle are actively carried out.

From the viewpoint of energy density, LiCoO ₂ currently used has a problem that it is difficult to realize a high voltage. Therefore, new materials that can replace these materials are being studied, and the most notable material is Mn-based lithium oxide.

However, when a cell using a spinel-structured positive electrode active material is left at a high temperature in a charged state, a conventional LiPF ₆ lithium salt is decomposed to generate HF, thereby causing elution of metal ions. In addition, precipitation reaction of the eluted metal ions on the surface of the cathode causes problems such as an increase in cathode potential and a decrease in cell OCV (open-circuit voltage), which deteriorates cycle performance and high-temperature storage characteristics.

The present invention reduces the dissolution phenomenon of metal ions at high temperatures and reduces precipitation of metal ions on the surface of the anode plate by forming a film on the surface of the anode, thereby reducing the OCV (Open Circuit Voltage) phenomenon The present invention is directed to providing a positive electrode for a lithium secondary battery and a secondary battery comprising the same.

In order to solve the problems of the present invention, the present invention provides a nonaqueous organic solvent; Lithium salts; And an aromatic amine derivative as an additive, and provides a high-voltage lithium secondary battery having an operating voltage of 4.3 V or higher.

According to the present invention, the amine derivative captures HF generated due to the decomposition of the lithium salt dissolved in the electrolyte solution, thereby preventing Mn elution and the like in the anode, thereby improving the high-temperature storage characteristics and the life characteristics.

Particularly, improvement of battery characteristics is more remarkable at high voltage.

In particular, when an aromatic amine derivative is included, Mn elution due to HF formation can be fundamentally blocked due to the ability to capture HF and the ability to form SEI film on the surface of the electrode plate, and the high temperature storage characteristics such as OCV Open Circuit Voltage) can be improved.

1 is a partial cross-sectional view of a cylindrical battery according to an embodiment of the present invention.
FIG. 2 is a graph of a cell assembled in a circular cell of 18650 according to Example 1 of the present invention and Comparative Example 1, according to the method of Experimental Example 1. FIG.
FIG. 3 is a graph of a cell assembled with 2016 coin pull cells according to Example 1 and Comparative Example 1, according to the method of Experimental Example 2. FIG.
4 is a graph showing the results of experiments of the battery assembled with the 18650 round cell according to the method of Experimental Example 2 according to Example 1 and Comparative Example 1 of the present invention.
FIG. 5 is a graph showing a result of an experiment of Example 1 and Comparative Example 1 of a cell assembled in a 18650 round cell according to the method of Experimental Example 2. FIG.
6 is a graph showing the GC-MS analysis of the retention time of the electrolytic solution to which the pyridine additive was added according to Experimental Example 3, according to an embodiment of the present invention.

Hereinafter, the present invention will be described more specifically.

The electrolyte for a high-voltage lithium secondary battery according to an embodiment of the present invention includes a non-aqueous organic solvent; Lithium salts; And an aromatic amine derivative as an additive, and is used for a lithium secondary battery having an operating voltage of 4.3 V or higher.

According to an embodiment of the present invention, the aromatic amine derivative may be added to the electrolyte solution so as to capture HF generated by the decomposition of the lithium salt. According to one embodiment of the present invention, a substituted or unsubstituted pyridine derivative having 5 to 30 carbon atoms is preferably used.

According to an embodiment of the present invention, the aromatic amine derivative is preferably a pyridine derivative represented by the following formula (1).

[Chemical Formula 1]

R 1, R 2, R 3, R 4 and R 5 are each an alkyl group having 1 to 6 carbon atoms or an aromatic group having 6 to 18 carbon atoms, -F, -O, -N or -CF 3.

In particular, pyridine exhibits excellent effects in a high-voltage lithium secondary battery operating at 4.3 V or higher. According to an embodiment of the present invention, the high-voltage lithium secondary battery has an operating voltage of 4.3V to 5V, more preferably 4.35V to 4.8V.

In a secondary battery having an operating voltage lower than 4.3 V, there is no significant difference according to the addition of the amine derivative, especially pyridine. However, in a secondary battery having an operating voltage of 4.3 V or higher, high temperature storage and lifetime characteristics are rapidly increased .

According to an embodiment of the present invention, it is preferable that the amine derivative is contained in an amount of 0.05 wt% to 8 wt% with respect to the non-aqueous organic solvent. When the additive is added in a small amount, the effect of trapping HF is reduced, and when the additive is added in an excess amount, the capacity of the battery decreases.

The electrolyte solution further comprises a lithium salt and a non-aqueous organic solvent. The lithium salt acts as a source of lithium ions in the battery to enable operation of a basic lithium battery. The non-aqueous organic solvent is used for an electrochemical reaction And the ions that are involved in the ion exchange can be moved.

The lithium salt _{LiPF 6, LiBF 4, LiSbF 6} , LiAsF 6, LiN (SO 2 C 2 F 5) 2, Li (CF 3 SO 2) 2 N, LiN (SO 3 C 2 F 5) 2, LiC 4 _{F 9 SO 3, LiClO 4,} LiAlO 2, LiAlCl 4, LiN (C x F 2x +1 SO 2) (C y F 2y +1 SO 2) ( where, x and y are natural numbers), LiCl, LiI, and LiB (C ₂ O ₄ ) ₂ (lithium bis (oxalato) borate (LiBOB)) may be selected.

Since the pyridine derivative according to the present invention can form a film on the surface of the positive electrode, the lithium salt other than the fluorine-based lithium salt has a high-temperature storage effect. Preferably, the positive-electrode coating film as well as the HF are removed from the fluorine-based lithium salt, so that a more preferable effect can be obtained.

According to one embodiment of the present invention, the concentration of the lithium salt is preferably in the range of 0.6M to 2.0M, more preferably in the range of 0.7 to 1.6M, relative to the non-aqueous organic solvent. If the concentration of the lithium salt is less than 0.6M, the conductivity of the electrolyte decreases and the performance of the electrolyte deteriorates. If the concentration exceeds 2.0M, the viscosity of the electrolyte increases and the mobility of the lithium ion decreases.

As the non-aqueous organic solvent, carbonate, ester, ether or ketone may be used alone or in combination. Examples of the carbonate include dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate (DPC), methyl propyl carbonate (MPC), ethyl propyl carbonate (EPC), methyl ethyl carbonate (MEC) (GBL), n-methyl acetate, n-ethyl acetate, n-propyl acetate, and the like can be used as the ester. , And the ether may be dibutyl ether or the like, but is not limited thereto.

The non-aqueous organic solvent may further include an aromatic hydrocarbon organic solvent. Specific examples of the aromatic hydrocarbon organic solvent include benzene, fluorobenzene, bromobenzene, chlorobenzene, cyclohexylbenzene, isopropylbenzene, n-butylbenzene, octylbenzene, toluene, xylene and mesitylene Which may be used alone or in combination.

The present invention provides a lithium secondary battery comprising a cathode, a cathode, a separator and an electrolyte according to the present invention.

<Anode>

The positive electrode may be prepared by mixing a positive electrode active material, a positive electrode active material, a conductive agent and a binder of the present invention with a solvent to form a slurry, applying the slurry to the positive electrode current collector, and drying and pressing. If necessary, a filler or a viscosity controlling agent may be further added.

As the positive electrode collector, metals such as aluminum, copper, nickel, silver, and stainless steel, and alloys of these metals may be used. Normally, aluminum or an aluminum alloy is used as the positive electrode collector. The positive electrode collector is generally made to have a thickness of 3 to 500 mu m.

The cathode active material may be a conventional cathode active material that can be used for a cathode of a conventional secondary battery, and preferably a spinel cathode active material may be used.

Examples of such a cathode active material include at least one lithium manganese-based active material selected from the group consisting of the following chemical formulas (2) to (15), a rhodium nickel cobalt manganese chemical active material of formula (16), a phosphoric acid- .

(2)

LiMnA ₂

(3)

LixMnA ₂

[Chemical Formula 4]

LiMnO _{2 - z} A _z

[Chemical Formula 5]

Li _x MnO _{2 - z} A _z

[Chemical Formula 6]

LiMn _{1 - y} M _y A ₂

(7)

Li _x Mn _{1 - y} M _y A ₂

[Chemical Formula 8]

LiMn ₂ A ₄

[Chemical Formula 9]

Li _x Mn ₂ O ₄

[Chemical formula 10]

LiMn ₂ O _{4 - z} A _z

(11)

Li _x Mn ₂ O _{4 - z z}

[Chemical Formula 12]

LiMn _{2 - y} M _y A ₄

[Chemical Formula 13]

Li _x Mn _{2 - y} M _y A ₄

Wherein M is at least one element selected from the group consisting of Al, Cr, Co, Mg, La, Ce, Sr, and V, wherein, in the above Formulas 1 to 12, 1.0 ≦ x ≦ 1.2, 0.01 ≦ y ≦ 0.1, and 0.01 ≦ z ≦ 0.5. Transition metal or lanthanide metal, and A is selected from the group consisting of O, F, S and P.)

[Chemical Formula 14]

Li _{1 + x} Ni _y Mn _{1 - y - z} M _z O ₂

(At least one selected from the group consisting of 0? X <0.2, 0.4? Y? 0.6, 0? Z? 0.2, M = Co, Al, Ti, Mg,

 [Chemical Formula 15]

Li _{1 + x} Ni _y Mn _{2 - y - z} M _z O _{4 + w}

(At least one selected from the group consisting of 0? X <0.2, 0.4? Y? 0.6, 0? Z? 0.2, 0? W? 0.1, M = Al, Ti, Mg,

[Chemical Formula 16]

Li _{1 + z} Ni _b Mn _c Co _{1 - (b + c)} O ₂

(0? Z <0.1, 0.2? B? 0.7, 0.2? C? 0.7, b + c <1 in the above formula)

[Chemical Formula 17]

LiCoPO4

[Chemical Formula 18]

LiFePO4

Since the electrolyte according to the present invention is preferably used for a battery operating at a high voltage, the LCO active material may be preferably used as the active material of the formulas (14) to (18) having high voltage characteristics because of the possibility of structural collapse upon charging to a high voltage.

The positive electrode active material may also have a coating layer on the surface of the compound.

As the solvent, a non-aqueous solvent or an aqueous solvent is used. Examples of the non-aqueous solvent include N-methyl-2-pyrrolidone (NMP), dimethylformamide, dimethylacetamide, N, N-dimethylaminopropylamine, ethylene oxide and tetrahydrofuran.

The binder may be any material as long as it can adhere the positive electrode active material particles to each other and adhere the positive electrode active material to the current collector. Representative examples of the binder include polyvinyl alcohol, carboxymethyl cellulose, hydroxypropyl cellulose, polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, a polymer containing ethylene oxide, polyvinyl pyrrolidone, polyurethane, But are not limited to, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, styrene-butadiene rubber, acrylated styrene-butadiene rubber, epoxy resin and nylon. Preferably, the binder may be polyvinylidene fluoride.

The conductive agent is used for imparting conductivity to the electrode. Any conductive material that does not cause a chemical change can be used in the battery. The conductive agent may be added in an amount of 1 to 30 wt% based on the total weight of the electrode material mixture . Typical examples of the conductive agent include copper-based materials such as natural graphite, artificial graphite, carbon black, acetylene black, ketjen black and carbon fiber, metal powders such as nickel, aluminum and silver, and metal- Of a conductive polymer or a mixture thereof may be used.

The filler is an auxiliary component for suppressing the expansion of the electrode. The filler is not particularly limited as long as it is a fibrous material without causing a chemical change in the battery, and examples thereof include olefin polymers such as polyethylene and polypropylene; Fibrous materials such as glass fibers and carbon fibers are used.

The viscosity adjusting agent may be added up to 30% by weight based on the total weight of the electrode mixture, so as to control the viscosity of the electrode mixture so that the mixing process of the electrode mixture and the coating process on the collector may be easy. Examples of such viscosity modifiers include carboxymethylcellulose, polyvinylidene fluoride and the like, but are not limited thereto. In some cases, the solvent used in the preparation of the positive electrode slurry may play a role as a viscosity adjusting agent.

<Cathode>

The negative electrode includes a negative electrode active material capable of inserting and desorbing lithium ions. The negative electrode can be produced by dispersing a negative electrode active material, a binder and a conductive agent in a solvent to prepare a slurry composition, and applying the slurry composition to an anode current collector.

The negative electrode active material is composed of any one or a combination of two or more materials selected from the group consisting of a material capable of reversibly storing and releasing lithium, a metal material capable of alloying with lithium, and a mixture thereof. Examples of the material capable of reversibly occluding and desorbing lithium include at least one material selected from the group consisting of artificial graphite, natural graphite, graphitized carbon fiber, graphitized mesocarbon microbead, fullerene, and amorphous carbon. . Examples of the amorphous carbon include hard carbon, coke, and MCMB and MPCF calcined at 1500 ° C or lower. At least one metal selected from the group consisting of Al, Si, Sn, Pb, Zn, Bi, In, Mg, Ga, Cd and Ge is exemplified as the metal capable of being alloyed with lithium. These metal materials may be used singly or as a mixture or alloyed. In addition, the metal may be used as a composite material mixed with a carbon-based material.

The negative electrode plate is formed by applying a negative electrode slurry obtained by mixing and dispersing a negative electrode mixture in a solvent to an anode current collector, and drying and rolling the same.

Examples of the anode current collector include punching metal, x-punching metal, gold foil, foamed metal, sintered metal fiber cloth, nickel foil and copper foil.

The solvent, the binder and the conductive agent may be the same as the cathode active material slurry.

< Separator >

The lithium secondary battery may include a separator to prevent a short circuit between the positive electrode and the negative electrode and to provide a path for the lithium ion. Such a separator may include a polypropylene, a polyethylene, a polyethylene / polypropylene, a polyethylene / polypropylene / Polyolefin-based polymer membranes such as propylene / polyethylene / polypropylene, or multi-membranes thereof, microporous films, woven fabrics, and nonwoven fabrics. A film having a porous polyolefin film coated with a resin having excellent stability or a ceramic material having excellent heat resistance may also be used. When a solid electrolyte such as a polymer is used as an electrolyte, the solid electrolyte may also serve as a separation membrane.

The separator is interposed between the positive electrode and the negative electrode, and an insulating thin film having high ion permeability and mechanical strength is used. The pore diameter of the separator is generally 0.01 to 10 mu m and the thickness is generally 5 to 300 mu m.

The lithium secondary battery can be classified into a lithium ion battery, a lithium ion polymer battery, and a lithium polymer battery depending on the type of the separator and electrolyte used. The lithium secondary battery can be classified into a cylindrical shape, a square shape, a coin shape, Depending on the size, it can be divided into bulk type and thin type. The structure and the manufacturing method of these batteries are well known in the art, so that detailed description thereof will be omitted.

According to another embodiment of the present invention, there is provided a lithium secondary battery including the negative electrode.

The lithium secondary battery can be classified into a lithium ion battery, a lithium ion polymer battery, and a lithium polymer battery according to the type of a separator and an electrolyte to be used. The lithium secondary battery can be classified into a cylindrical shape, a square shape, a coin shape, Depending on the size, it can be divided into bulk type and thin type.

1 is an exploded perspective view of a lithium secondary battery according to an embodiment of the present invention. FIG. 1 shows a configuration of a cylindrical battery according to the present invention. However, it is needless to say that the battery of the present invention is not limited to FIG. 1 but may be square or pouch type.

The structure and manufacturing method of the cells other than the cylindrical battery are well known in the art, and detailed description thereof will be omitted.

1, the lithium secondary battery 100 has a cylindrical shape and includes a cathode 112, a cathode 114, a separator 113 disposed between the cathode 112 and the anode 114, A main part is an electrolyte (not shown) impregnated into the cathode 112, the anode 114 and the separator 113, a battery container 120, and a sealing member 140 for sealing the battery container 120 Consists of. The lithium secondary battery 100 is constructed by laminating a cathode 112, an anode 114 and a separator 113 in this order and then winding them in a spiral wound state in the battery container 120.

The cathode 112, the anode 114, the separator 113, and the electrolytic solution are the same as those described above.

Hereinafter, embodiments of the present invention will be described in more detail with reference to examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

Example  One

The particle size of 10㎛ LiNi _{0 .5} Mn _{1 .5} O ₄ positive electrode active material, carbon-based conductive agent and a binder polyvinylidene fluoride 94: 3: a mixture of NMP in a weight ratio of 3 to form a slurry, and aluminum Cast on a thin plate, dried in a vacuum oven at 120 캜, and rolled to prepare a positive electrode and used as a negative electrode plate of graphite (MAG V4).

A 18650 and 2016 type lithium secondary battery was fabricated by supplying a non-aqueous electrolyte through a separator made of polypropylene having 18 mu m to the obtained positive electrode and negative electrode. As the non-aqueous electrolyte, a nonaqueous electrolyte solution in which 1.15 M LiPF 6 was dissolved in EC / EMC / DMC = 3/3/4 (weight fraction) was used.

As an electrolyte additive, pyridine was added in an amount of 1 wt% based on the non-aqueous electrolyte.

The anode / cathode / membrane / electrolyte compositions used in the 2016 and 18650 cells are the same.

Example  2 to 8

A lithium secondary battery was prepared in the same manner as in Example 1, except that the non-aqueous electrolyte prepared by varying kinds and contents of additives according to the following Table 1 was used.

The particle size of 10㎛ LiNi _{0 .5} Mn _{1 .5} O ₄ positive electrode active material, carbon-based conductive agent and a binder polyvinylidene fluoride 94: 3: a mixture of NMP in a weight ratio of 3 to form a slurry, and aluminum Cast on a thin plate, dried in a vacuum oven at 120 캜, and rolled to prepare a positive electrode and used as a negative electrode plate of graphite (MAG V4).

A separator made of polypropylene of 18 mu m was interposed between the obtained positive electrode and negative electrode, and a nonaqueous electrolyte was supplied to prepare a lithium secondary battery in the form of a 2016 coin cell. As the non-aqueous electrolyte, a nonaqueous electrolyte solution in which 1.15 M LiPF 6 was dissolved in EC / EMC / DMC = 3/3/4 (weight fraction) was used.

As an electrolyte additive, pyridine 1 and pyridine derivatives 1, 2 and 3 were added in an appropriate amount to the non-aqueous electrolyte.

[Chemical Formula 19]

[Chemical Formula 20]

[Chemical Formula 21]

additive Active material Kinds content
(wt%) Example 2 Pyridine 0.1 LiNi _{0 .5} Mn _{1 .5} O ₄ Example 3 Pyridine 2 LiNi _{0 .5} Mn _{1 .5} O ₄ Example 4 Pyridine 8 LiNi _{0 .5} Mn _{1 .5} O ₄ Example 5 Pyridine 0.05 LiNi _{0 .5} Mn _{1 .5} O ₄ Example 6 The pyridine derivative of formula 19 2 LiNi _{0 .5} Mn _{1 .5} O ₄ Example 7 The pyridine derivative of formula 20 2 LiNi _{0 .5} Mn _{1 .5} O ₄ Example 8 The pyridine derivative of formula 21 2 LiNi _{0 .5} Mn _{1 .5} O ₄

Comparative Example  One

The procedure of Example 1 was repeated except that the amine derivative was not added as an additive to the electrolytic solution.

<Battery performance evaluation>

FIGS. 2, 4, and 5 are results obtained after assembling the cells into 18650 cells (Comparative Example 1, Example 1). FIG. 3 shows the result of evaluation after assembling with 2016 coin pull cells (Comparative Example 1, Examples 1-8).

Experimental Example 1: High Temperature Storage Evaluation at 4.2 V Operating Voltage The high temperature storage test of the 18650 circular cell type battery prepared in the Examples and Comparative Examples was performed at 60 占 폚.

First, the charge / discharge of Mars was carried out twice with 0.2C / 0.5C, and the standard charge / discharge current density was 0.5C / 0.2C, charge end voltage was 4.2V (Li / graphite), discharge end voltage was 3.0V / Graphite) was performed once each time.

The charging current for high-temperature storage at 60 ° C was measured at 0.5 ° C and then stored at 60 ° C in a constant-temperature chamber for 30 days.

These results are shown in Fig.

As can be seen from FIG. 2, at 4.2 V, no significant difference was observed at high temperature storage regardless of addition of the aromatic amine derivative.

Experimental Example  2: High temperature storage evaluation at 4.8V operating voltage

The high temperature storage test of the 2016 circular cell type cell prepared in Examples and Comparative Examples was performed at 60 캜.

The charging end voltage was 4.8 V (Li / graphite), and the same procedure as in Experimental Example 1 was carried out.

The results are shown in Figs.

According to FIG. 3, Comparative Example 1, which does not contain an aromatic amine derivative as an additive, exhibits a rapid voltage drop 10 days before storage at high temperature. However, the cells of Examples 1 to 5 containing an aromatic amine derivative have a delayed OCV drop Effect is shown. However, the effect of addition of the additive in Example 5, which is added in a small amount, is not significant, and in Example 8 in which the excess amount is added, it is understood that the effect does not increase proportionally with addition of excess amount. This is because the increase of the amount of the additive causes the increase of the positive electrode coating.

According to FIG. 4, when a battery employing a 5V-level spinel active material is left at a high temperature, internal pressure increases due to decomposition of the electrolyte, thereby causing CID open, resulting in cell death. However, when the amine derivative is used as an additive, the electrolyte decomposition is delayed and the resistance increase is decreased, which shows that OCV drop is delayed.

5, the battery according to Comparative Example 1 exhibited a large increase in resistance of 95 m? With CID open after 3 days, whereas Example 1 in which 1% by weight of pyridine as an amine derivative was added showed a 10-day OCV CID open after maintenance. After 5 days, the resistance was 45 mΩ, which was about twice as low as that of the reference electrolyte.

Experimental Example  3: When pyridine was added retention time  Confirm

The presence of additive was confirmed by GC-MS analysis. The position of the pyridine peak from the electrolyte itself added with pyridine 10wt% was confirmed at the retention time of 3 minutes, and the cell containing 10wt% The results are shown in Fig. 6. Measurement conditions of the GC-MS are as follows. GC-MS (GC: Agilent 6890, detector: Agilent 5973 mass detector)

-. oven: 10 ° C / min, 40 ° C (5 min) to 250 ° C (10 min)

-. inlet 290 ^o C, split 1:50

-. mass range: 10 ~ 500 amu

Claims (10)

A high-voltage lithium secondary battery having an operating voltage of 4.3 V or higher,
Electrolytic solution;
A positive electrode comprising a positive electrode active material capable of inserting and desorbing lithium ions;
And a negative electrode including a negative electrode active material capable of inserting and desorbing lithium ions,
Here,
Non-aqueous organic solvent;
Lithium salts; And
An aromatic amine derivative represented by the general formula (1) as an additive,
[Chemical Formula 1]

Wherein R ₁ , R ₂ , R ₃ , R ₄ and R ₅ are each an alkyl group having 1 to 6 carbon atoms or an aromatic group having 6 to 18 carbon atoms, -F or -CF ₃ ,
Wherein the cathode active material comprises at least one of the following formulas 14 to 18:
[Chemical Formula 14]
Li _{1 + x} Ni _y Mn _{1 -yz} M _z O ₂
(At least one selected from the group consisting of 0? X <0.2, 0.4? Y? 0.6, 0? Z? 0.2, M = Co, Al, Ti, Mg,
[Chemical Formula 15]
Li _{1 + x} Ni _y Mn _{2 -yz} M _z O _{4 + w}
At least one selected from the group consisting of 0? X <0.2, 0.4? Y? 0.6, 0? Z? 0.2, 0? W? 0.1 and M = Al, Ti, Mg,
[Chemical Formula 16]
Li _{1 + z} Ni _b Mn _c Co _{1- (b + c)} O ₂
(Where 0? Z <0.1, 0.2? B? 0.7, 0.2? C? 0.7, and b + c <1 in the above formula)
[Chemical Formula 17]
LiCoPO ₄
[Chemical Formula 18]
LiFePO4. &Lt; / _RTI &gt; delete delete delete The method according to claim 1,
Wherein the aromatic amine derivative is contained in an amount of 0.05 wt% to 8 wt% with respect to the non-aqueous organic solvent. The method according to claim 1,
Wherein the high-voltage lithium secondary battery has an operating voltage of 4.3V to 5V. The method according to claim 1,
Wherein the high-voltage lithium secondary battery has an operating voltage of 4.35V to 4.8V. The method according to claim 1,
The lithium salt is _{LiPF 6, LiBF 4, LiSbF 6} , LiAsF 6, and _{LiN (SO 2 C 2 F 5} ) 2 group or a high-voltage lithium secondary battery, characterized in that more than one selected from consisting of. delete delete

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